1. Field of the Invention
The present invention relates to a protective member for protecting the front side of a wafer such as a semiconductor wafer and also to a wafer processing method using the protective member, such as grinding of the wafer.
2. Description of the Related Art
In a semiconductor device fabrication process, a plurality of devices having electronic circuits are formed on the front side of a semiconductor wafer, and the back side of the semiconductor wafer is ground to reduce the thickness of the semiconductor wafer. Thereafter, the semiconductor wafer is divided into the individual devices. In general, back grinding of the wafer is performed by a method including the steps of holding the wafer on a holding table in the condition where the back side of the wafer is exposed and next grinding the back side of the wafer held on the holding table by using abrasive members of grinding means. If the front side of the wafer comes into direct contact with the holding table in performing this method, the devices formed on the front side of the wafer may be damaged. Therefore, a protective member is attached to the front side of the wafer to protect the devices prior to holding the wafer on the holding table.
Examples of the protective member known in the art include a protective tape disclosed in Japanese Patent Laid-open No. Hei 05-198542 and a wafer support system disclosed in Japanese Patent Laid-open No. 2004-207606. The protective tape is composed of a base sheet and an adhesive layer formed on one side of the base sheet. The protective tape is attached through its adhesive layer to the front side of the wafer. On the other hand, the wafer support system is usually attached to the wafer by using an adhesive.